Who has experienced this with their Lithium type batteries? What method do you use to wake the BMS, assuming your battery has the same issue as this one! Thanks for stopping by!
I have mavic pro batteries that wont charge. Is there a way to wake those up? The Mavic charger will not charge...kind of like in your video. Can you help?
@@W0KNI The batteries are a couple of years old...but never used. Just sat on the shelf. Voltage is zero. I think the BMS just turned them off. Is there anything to do to wake them up?
Normally I would say yes, but only if you could connect it to a same voltage source. The pinouts for your battery can be found on the internet. You might check this thread. forum.dji.com/thread-134111-1-1.html I see a suggestion there but not sure if that works with your battery. DJI has done a slick job of blocking you into using only THEIR batteries. Another option is to insert your "dead" battery into the drone then charge the drone via the cable. The internal circuit between the battery and the drone might "wake" it up. Good luck!
N6EF-This happened to me and I thought I damaged my battery. Thankfully, the BMS saved the battery. Using your method or one similar to it got me charging again. I keep a 9 volt battery in my POTA backpack so I can get just enough power into the battery to start the charging process. Thanks for some great information.
Hey Bill - thanks for watching! Glad it helped. When it first happened to me I was perplexed something so simple would take out a battery. Thankfully not so! Cheers.
Just tried this after my 100ah lifepo4 bms cut out on my golf cart. In less than a minute my battery showed voltage and is now charging correctly. Thank you sir.
Thank you! I've got a 20AH 12V Lifepo4 battery that wouldn't take a charge. I still don't understand how you can over deplete the battery, but not overcharge the battery, but that's what I did. If you have any thoughts on why we can over-deplete a battery, I'd love to see it in a future video, or link to a past video Anyway... I jump started my battery from my car battery for about a minute, then threw it on the charger, and it charged right up. Thank you so much for this!
Great to hear you brought it back to life! AFA overcharging, two things to note. One, the BMS should not allow this but cheap stuff fails this test. Second, your charger is another check point and should not allow this however it also depends on the battery BMS for feedback.
Been doing this since 2005 as a mechanic to get 12v lead acid batterys to charge as the chargers in the shop won't attempt to charge an already dead battery. Did the same recently with an 80v lithium battery that dropped below charger turn on voltage on an electric leaf blower.
Duuuuude you’re da man! I have a Renogy lifpo4 smart battery that was sitting stubborn at 2V. I did what you said mounting in parallel to my lead acid car battery with jumper cables for only about 10 sec. then I connected the lifpo4 charger and now it’s charging! THANK YOU!!!
You would think? However the BMS inside the battery box goes into a low voltage sleep mode that unfortunately tells the majority of chargers the battery won’t take a charge. The method I show applies enough current to essentially wake up the BMS so the battery can be charged
Was just wondering. Can you hook up the charger to the Lithium battery, which I understand will not charge because it"s internally shut down by the BMS and is reading 0 vdc and then just tap the pos and neg terminals with the LA battery? Wouldn't that turn on the charger? I have drilled holes, in strategic locations, in cordless tool batteries, that give access to the battery pack's terminals, to allow me to give them a short charge from a good battery to turn on the charger, but I can't do it while they are inserted in the charger. I have to "manually" send in the juice until I think the battery has charged enough to "trick" the charger into turning on, which I think is what you are suggesting with your larger battery. Seems that if you can connect your charger up to the Lithium battery ahead of time, with the + and - terminals still exposed, just one little burst of a viable voltage would get the charger turned on. Am I wrong?
Hey John - thanks for checking on the vid. Interesting approach you are describing and I've honestly not tried combining the two. I suppose it wouldn't hurt your charger. Thanks for the tip, next time I have this issue I'll try to remember to give it a go! Cheers.
You are just describing an overly complicated version of what is in the video. The end goal is to show the charger enough voltage to turn on and charge the battery. You can do that by putting the charge in the battery which wakes the BMS and allows raising of the battery voltage and then connecting to a charger. Drilling holes and connecting wires to your charger is just an extra step and extra parts to reach the same result.
@@btwbrand Not in this case. I was dealing with a particular 18 Volt Ryobi battery and I have to say, I don't remember if it is the grey kind or the ones with the green stalk that contains the terminals, Ryobi has made a few different kinds over the years. In any event, when I tried to apply some voltage to the + and - terminals, nothing happened. No spark and no impact on whether it charged in the charger. I assumed that something had to be sensed via the third unlabeled terminal in order to open a gate or bypass a diode or something like that to get juice into the battery. That's when I took the battery apart to gain access to the + and - terminals of the actually cell pack. That worked, so I drilled 2 tiny holes in the plastic outer case to let me touch a pair of push pins with wires attached to those internal terminals without disassembling the case each time. Any ideas on why that was necessary? Maybe an open circuit on the thermal switch? Whatcha think?
Got my lifepo4 20amp battery awoken. I connected it to my Sharmans 30amp power supply. It has variable voltage so dropped it to 12.5v and connected to the psu for 1m 30secs and it will now charge 🙂
this is normal BMS behaviour. Its when you leave it like this for a year then try to wake it up that you really need to wake up the bms........... thats a great field expedient way to wake it back up for recharging. Are you certain that this BMS limits current in during charging ? have you tried to charge it on a huge power supply to measure the current? most BMS , especially cheap ones will not be CC during charging and reply on the charger to limit the current.
I have 2 lifePO4 12v 8Ah I bought the first of this month. I bought a charge you have to set type of battery number of cells, voltage, etc. I tried to see the charger work. When I hook either battery up and try to start the charge I get a cell warning on both and no charge. My other charger gives me a cell balance problem. What do you think? I just got one of the Miady 20ah batteries today. The charger is at my office so haven’t had a chance to try it with either charger.
Hey Dr. Hughes - thanks for watching. If you're using the same or similar charger as you saw in my video, you will be prompted with a warning that no balance lead was detected after selected the START menu item. For this warning you will select YES and continue. At that point it should run as expected. Let me know if that helps!
Thanks a lot for the video, I have another question, if the battery were short circuit shortly after fully charged. And the BMS kicked in, can i use the same method to wake up the battery? Thanks again!
Hey there! Thanks for watching. Very good question and really depends on the quality of the BMS. If it survived then yes, you should be able to "wake it up" using this method, but again your results may vary depending on if the BMS was able to stop the over discharge surge. Let me know how it works out for you!
@@W0KNI Thanks a lot Stephen! i do not have a lead acid battery in hand, so i connected to another same LiFePO4 battery, positive to positive and negative to negative for 1min, nothing happened~ still no voltage at all.
I have a 12 volt, 100ah lithium lifepo4 battery that drained down to 3.7 volts. I keep reading that if I attempt to recharge it, it could catch fire. Is this true? Would your method above work for a battery that size?
Thanks for checking out my video. Sorry about your battery. Using the method shown in the video, your battery will not catch on fire - unless your cells are physically damaged. If they are leaking then do not try to charge the battery. However, if it was just drained down to 3.7 volts then try this method to wake the BMS. Let me know how it goes for you.
Hello Stephen, should this also work with a 48 volt 20 Ah battery from an electric scooter (EVOmaxx)? And do I need a 48 V second battery as well? The repairshop asks €850 to fix it. Ad Netherlands
Hey Ad - Good question, and the answer is - probably. However the basic concept is that you apply enough voltage to get your BMS to "wake up." HOWEVER, the dead battery could easily have MORE than 12 volts hiding behind the sleeping BMS. So the problem is if you "wake-up" your BMS and then you have 48 volts that will try to feed into your other battery - THIS IS BAD. And should not be done. I don't know what kind of battery system you have but for $850 euro's I would think you could buy a new one OR buy 4 x 12v batteries in series to get to 48 volts and try to connect it to your dead battery. I hope this helps.
Im in the same boat. Im charging up 4 12v batteries and plan to wire in series to try this. I ran my battery dead and it took a charge but seemed goofy. Voltmeter started acting goofy and I really don't think I was getting the correct voltage on my reading. Now it's dead and won't accept a charge. It's sitting at around 2.5 volts. I'll let you know but curious if you tried it.
@@adjekratje1 well crap. i put my battery on the bench and got all my connectors wired up and before connecting did one last volt check and now it's reading 54 volts. I wonder if my wiring or something screwy with my controller is causing the problem.
I am having a charging issue. I am using one of those selectable sla/lifepo4 chargers and the light stays red constantly, never turns green. When I take the battery off it drops fast.
Hey Matt - thanks for watching! What are the specs on your battery? Using a MM, what does the voltage say at the terminals? It could be that you have a bad cell, this happens for many reasons. In such a case your battery is best to be discharged and recycled. Let me know!
@@W0KNI When I take it of the charger, it reads 13.45. But I hook a usb hub to it, and just trying to charge a cell phone drops it fast to 12.8 within 15 minutes. Its the Miady 8ah battery.
@@usarmyfl1 ahh. Ok. So for that battery the nominal voltage is 12.8v. If you have something to plug into that draws about 1A then the battery should perform for about 7.5 hours before the min. voltage cutoff kicks in by the BMS. Usually after your voltage drops under 11v that’s when your Life battery is about depleted.
@@W0KNI The thing is, if I look at a lifepo4 voltage chart, 12.8 shows about 17% capacity left, when the battery should be near 100% That's what confuses me.
Hey there, thanks for watching. Sounds like great info, do you have a model you can share? I'm always interested in good battery tech. I use a pretty reputable charger for Lithium batteries and it was unable to kick start my "sleeping" battery. take care!
Who has experienced this with their Lithium type batteries? What method do you use to wake the BMS, assuming your battery has the same issue as this one! Thanks for stopping by!
I have mavic pro batteries that wont charge. Is there a way to wake those up? The Mavic charger will not charge...kind of like in your video. Can you help?
@@flintdwiggins Hey there. What does a voltmeter say? How old is the battery?
@@W0KNI The batteries are a couple of years old...but never used. Just sat on the shelf. Voltage is zero. I think the BMS just turned them off. Is there anything to do to wake them up?
Normally I would say yes, but only if you could connect it to a same voltage source. The pinouts for your battery can be found on the internet. You might check this thread. forum.dji.com/thread-134111-1-1.html I see a suggestion there but not sure if that works with your battery. DJI has done a slick job of blocking you into using only THEIR batteries.
Another option is to insert your "dead" battery into the drone then charge the drone via the cable. The internal circuit between the battery and the drone might "wake" it up.
Good luck!
I use a charger that provides some voltage before going into charge mode.
You seem like a man I could be a best friend with! I thought my BMS was as useful as a _BM_ but with your help I fixed it!
Glad I could help! LOL Have a great day!
Yes Sir! 10 seconds treatment with lead acid battery connected, waked up my LiFePo4 too.
Lovely hack!
Thank you!
Glad it helped! Thanks for checking it out.
N6EF-This happened to me and I thought I damaged my battery. Thankfully, the BMS saved the battery. Using your method or one similar to it got me charging again. I keep a 9 volt battery in my POTA backpack so I can get just enough power into the battery to start the charging process. Thanks for some great information.
Hey Bill - thanks for watching! Glad it helped. When it first happened to me I was perplexed something so simple would take out a battery. Thankfully not so! Cheers.
Just tried this after my 100ah lifepo4 bms cut out on my golf cart. In less than a minute my battery showed voltage and is now charging correctly. Thank you sir.
Reno - so happy that worked for you! Those batteries are not cheap, glad this method got you going again.
You are awesome! Can confirm the BMS needs to be woken back up like this if Miady batteries short and overcurrent kicks in too.
Hey there! Great to hear that. I've heard about other batteries don't fare as well, but maybe Miady's BMS circuitry was better. Glad this helped!
@@W0KNI, yep thank you very much. It was an accidental short with my multimeter as I forgot that I had is set to current instead of Voltage.
Yup. Good tip. I use it all the time. I don't know of any other way to get the charging started
I agree, seems odd but glad its an option!
Thank you! I've got a 20AH 12V Lifepo4 battery that wouldn't take a charge. I still don't understand how you can over deplete the battery, but not overcharge the battery, but that's what I did. If you have any thoughts on why we can over-deplete a battery, I'd love to see it in a future video, or link to a past video
Anyway... I jump started my battery from my car battery for about a minute, then threw it on the charger, and it charged right up. Thank you so much for this!
Great to hear you brought it back to life! AFA overcharging, two things to note. One, the BMS should not allow this but cheap stuff fails this test. Second, your charger is another check point and should not allow this however it also depends on the battery BMS for feedback.
Been doing this since 2005 as a mechanic to get 12v lead acid batterys to charge as the chargers in the shop won't attempt to charge an already dead battery. Did the same recently with an 80v lithium battery that dropped below charger turn on voltage on an electric leaf blower.
It works great! Odd that BMS's haven't evolved to handle the situation. Cheers!
Duuuuude you’re da man! I have a Renogy lifpo4 smart battery that was sitting stubborn at 2V. I did what you said mounting in parallel to my lead acid car battery with jumper cables for only about 10 sec. then I connected the lifpo4 charger and now it’s charging! THANK YOU!!!
Sweet! So glad this helped.
@@W0KNI you saved me a bunch of time and money. Really appreciate this episode. This is what makes RUclips great
Interesting video. Wouldn't the charger wake up the battery since it supplies voltage to the battery?
Barry
You would think? However the BMS inside the battery box goes into a low voltage sleep mode that unfortunately tells the majority of chargers the battery won’t take a charge. The method I show applies enough current to essentially wake up the BMS so the battery can be charged
Was just wondering. Can you hook up the charger to the Lithium battery, which I understand will not charge because it"s internally shut down by the BMS and is reading 0 vdc and then just tap the pos and neg terminals with the LA battery? Wouldn't that turn on the charger? I have drilled holes, in strategic locations, in cordless tool batteries, that give access to the battery pack's terminals, to allow me to give them a short charge from a good battery to turn on the charger, but I can't do it while they are inserted in the charger. I have to "manually" send in the juice until I think the battery has charged enough to "trick" the charger into turning on, which I think is what you are suggesting with your larger battery. Seems that if you can connect your charger up to the Lithium battery ahead of time, with the + and - terminals still exposed, just one little burst of a viable voltage would get the charger turned on. Am I wrong?
Hey John - thanks for checking on the vid. Interesting approach you are describing and I've honestly not tried combining the two. I suppose it wouldn't hurt your charger. Thanks for the tip, next time I have this issue I'll try to remember to give it a go! Cheers.
You are just describing an overly complicated version of what is in the video. The end goal is to show the charger enough voltage to turn on and charge the battery. You can do that by putting the charge in the battery which wakes the BMS and allows raising of the battery voltage and then connecting to a charger.
Drilling holes and connecting wires to your charger is just an extra step and extra parts to reach the same result.
@@btwbrand Not in this case. I was dealing with a particular 18 Volt Ryobi battery and I have to say, I don't remember if it is the grey kind or the ones with the green stalk that contains the terminals, Ryobi has made a few different kinds over the years. In any event, when I tried to apply some voltage to the + and - terminals, nothing happened. No spark and no impact on whether it charged in the charger. I assumed that something had to be sensed via the third unlabeled terminal in order to open a gate or bypass a diode or something like that to get juice into the battery. That's when I took the battery apart to gain access to the + and - terminals of the actually cell pack. That worked, so I drilled 2 tiny holes in the plastic outer case to let me touch a pair of push pins with wires attached to those internal terminals without disassembling the case each time. Any ideas on why that was necessary? Maybe an open circuit on the thermal switch? Whatcha think?
@@btwbrand ty for explaining what he was doing ..
Got my lifepo4 20amp battery awoken. I connected it to my Sharmans 30amp power supply. It has variable voltage so dropped it to 12.5v and connected to the psu for 1m 30secs and it will now charge 🙂
Excellent! Have fun
this is normal BMS behaviour. Its when you leave it like this for a year then try to wake it up that you really need to wake up the bms........... thats a great field expedient way to wake it back up for recharging. Are you certain that this BMS limits current in during charging ? have you tried to charge it on a huge power supply to measure the current? most BMS , especially cheap ones will not be CC during charging and reply on the charger to limit the current.
I have 2 lifePO4 12v 8Ah I bought the first of this month. I bought a charge you have to set type of battery number of cells, voltage, etc. I tried to see the charger work. When I hook either battery up and try to start the charge I get a cell warning on both and no charge. My other charger gives me a cell balance problem. What do you think? I just got one of the Miady 20ah batteries today. The charger is at my office so haven’t had a chance to try it with either charger.
Hey Dr. Hughes - thanks for watching. If you're using the same or similar charger as you saw in my video, you will be prompted with a warning that no balance lead was detected after selected the START menu item. For this warning you will select YES and continue. At that point it should run as expected. Let me know if that helps!
Thanks a lot for the video, I have another question, if the battery were short circuit shortly after fully charged. And the BMS kicked in, can i use the same method to wake up the battery? Thanks again!
Hey there! Thanks for watching. Very good question and really depends on the quality of the BMS. If it survived then yes, you should be able to "wake it up" using this method, but again your results may vary depending on if the BMS was able to stop the over discharge surge. Let me know how it works out for you!
@@W0KNI Thanks a lot Stephen! i do not have a lead acid battery in hand, so i connected to another same LiFePO4 battery, positive to positive and negative to negative for 1min, nothing happened~ still no voltage at all.
Hmm. Are you able to charge it after that last step? If charging is unsuccessful then I’m afraid you will need to remove and replace the BMS.
@@W0KNI Yeah, I tried to charge it for 1min and still no response. I guess the BMS is broken. Anyway, thanks a lot, Stephen!
Can confirm this method worked when I overloaded my Miady and the bms kicked on.
Thank you! Thank you! Thank you! 😊
You’re welcome!
I have a 12 volt, 100ah lithium lifepo4 battery that drained down to 3.7 volts. I keep reading that if I attempt to recharge it, it could catch fire. Is this true? Would your method above work for a battery that size?
Thanks for checking out my video. Sorry about your battery. Using the method shown in the video, your battery will not catch on fire - unless your cells are physically damaged. If they are leaking then do not try to charge the battery. However, if it was just drained down to 3.7 volts then try this method to wake the BMS. Let me know how it goes for you.
Hello Stephen, should this also work with a 48 volt 20 Ah battery from an electric scooter (EVOmaxx)? And do I need a 48 V second battery as well?
The repairshop asks €850 to fix it.
Ad
Netherlands
Hey Ad - Good question, and the answer is - probably. However the basic concept is that you apply enough voltage to get your BMS to "wake up." HOWEVER, the dead battery could easily have MORE than 12 volts hiding behind the sleeping BMS. So the problem is if you "wake-up" your BMS and then you have 48 volts that will try to feed into your other battery - THIS IS BAD. And should not be done. I don't know what kind of battery system you have but for $850 euro's I would think you could buy a new one OR buy 4 x 12v batteries in series to get to 48 volts and try to connect it to your dead battery. I hope this helps.
Im in the same boat. Im charging up 4 12v batteries and plan to wire in series to try this. I ran my battery dead and it took a charge but seemed goofy. Voltmeter started acting goofy and I really don't think I was getting the correct voltage on my reading. Now it's dead and won't accept a charge. It's sitting at around 2.5 volts. I'll let you know but curious if you tried it.
@@scotmaciver I didn't try it. I've sent it to another repairshop, which claim to fix it for € 100. Hope they're right.
@@adjekratje1 well i got my 4 batteries set up and ready to try. Need to get my connectors on and see what happens. I'll report back.
@@adjekratje1 well crap. i put my battery on the bench and got all my connectors wired up and before connecting did one last volt check and now it's reading 54 volts. I wonder if my wiring or something screwy with my controller is causing the problem.
I am having a charging issue. I am using one of those selectable sla/lifepo4 chargers and the light stays red constantly, never turns green. When I take the battery off it drops fast.
Hey Matt - thanks for watching! What are the specs on your battery? Using a MM, what does the voltage say at the terminals? It could be that you have a bad cell, this happens for many reasons. In such a case your battery is best to be discharged and recycled. Let me know!
@@W0KNI When I take it of the charger, it reads 13.45. But I hook a usb hub to it, and just trying to charge a cell phone drops it fast to 12.8 within 15 minutes. Its the Miady 8ah battery.
@@usarmyfl1 ahh. Ok. So for that battery the nominal voltage is 12.8v. If you have something to plug into that draws about 1A then the battery should perform for about 7.5 hours before the min. voltage cutoff kicks in by the BMS. Usually after your voltage drops under 11v that’s when your Life battery is about depleted.
@@W0KNI The thing is, if I look at a lifepo4 voltage chart, 12.8 shows about 17% capacity left, when the battery should be near 100% That's what confuses me.
@@W0KNI Thanks for your help! :)
Proper LiFeP04 chargers will wake up your battery, you just have to give a minute for the process to take place.
Hey there, thanks for watching. Sounds like great info, do you have a model you can share? I'm always interested in good battery tech. I use a pretty reputable charger for Lithium batteries and it was unable to kick start my "sleeping" battery. take care!
well my Energie Stor Lifepo4 charger will not wake my dead 20a battery
Good to know! Did you try briefly connecting another 12v battery to it like I did in the video?
@@W0KNI I have in the past and that does work.
@@W0KNI hi. Do I need to hook up a battery of similar amps? People say a car battery is OK...